NAME    [Toc]    [Back]

       ethers, ether_ntoa, ether_aton, ether_ntohost, ether_hostton,
 ether_line - Ethernet address mapping operations

SYNOPSIS    [Toc]    [Back]

       #include <sys/types.h>  #include  <sys/socket.h>  #include
       <net/if.h>      #include      <netinet/in.h>      #include
       <netinet/if_ether.h>

       char *ether_ntoa(
               struct  ether_addr   *e   );   struct   ether_addr
       *ether_aton(
               char *s ); ether_ntohost(
               char *hostname,
               struct ether_addr *e ); ether_hostton(
               char *hostname,
               struct ether_addr *e ); ether_line(
               char *l,
               struct ether_addr *e,
               char *hostname );

   Arguments    [Toc]    [Back]
       The     ether_addr     structure     is     defined     in
       <netinet/if_ether.h>

DESCRIPTION    [Toc]    [Back]

       These routines are useful for mapping 48-bit Ethernet numbers
 to their ASCII representations or their corresponding
       host names, and vice versa.  The mapping is obtained  from
       the /etc/ethers database; see ethers(4).

       The  function ether_ntoa() converts a 48-bit Ethernet number
 pointed to by e to its standard ACSII  representation;
       it  returns a pointer to the ASCII string. The representation
 is of the form: x : x : x : x : x : x

       Where x is a hexadecimal number between 0 and ff.

       The function ether_aton() converts an ASCII string in  the
       standard  representation back to a 48-bit Ethernet number;
       the function returns NULL if the string cannot be  scanned
       successfully.

       The  function  ether_ntohost()  maps  an  Ethernet  number
       (pointed to by e) to its associated hostname.  The  string
       pointed  to  by  hostname  must be long enough to hold the
       hostname and a NULL character. The function  returns  zero
       upon success and nonzero upon failure.

       Inversely,  the  function  ether_hostton() maps a hostname
       string to its corresponding Ethernet number; the  function
       modifies the Ethernet number pointed to by e. The function
       also returns zero upon success and nonzero upon failure.

       The function ether_line() scans a line (pointed to  by  l)
       and  sets the hostname and the Ethernet number (pointed to
       by e). The string pointed to  by  hostname  must  be  long
       enough  to  hold  the  hostname  and a NULL character. The
       function returns zero upon success and nonzero upon  failure.
   The  format  of  the  scanned  line is described by
       ethers(4).

FILES    [Toc]    [Back]

       Database that maps Ethernet addresses to hostnames

SEE ALSO    [Toc]    [Back]

       Commands: rarpd(8)

       Files: packetfilter(7), ethers(4)



                                                        ethers(3)